<?php

/*
 * This file is part of SwiftMailer.
 * (c) 2004-2009 Chris Corbyn
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

/**
 * Handles Quoted Printable (QP) Transfer Encoding in Swift Mailer.
 *
 * @package    Swift
 * @subpackage Mime
 * @author     Chris Corbyn
 */
class Swift_Mime_ContentEncoder_QpContentEncoder extends Swift_Encoder_QpEncoder implements Swift_Mime_ContentEncoder
{
	protected $_dotEscape;

	/**
	 * Creates a new QpContentEncoder for the given CharacterStream.
	 *
	 * @param Swift_CharacterStream $charStream to use for reading characters
	 * @param Swift_StreamFilter $filter if canonicalization should occur
	 * @param boolean $dotEscape if dot stuffing workaround must be enabled
	 */
	public function __construct(Swift_CharacterStream $charStream, Swift_StreamFilter $filter = null, $dotEscape = false)
	{
		$this->_dotEscape = $dotEscape;
		parent::__construct($charStream, $filter);
	}

	public function __sleep()
	{
		return array('_charStream', '_filter', '_dotEscape');
	}

	protected function getSafeMapShareId()
	{
		return get_class($this) . ($this->_dotEscape ? '.dotEscape' : '');
	}

	protected function initSafeMap()
	{
		parent::initSafeMap();
		if ($this->_dotEscape) {
			/* Encode . as =2e for buggy remote servers */
			unset($this->_safeMap[0x2e]);
		}
	}

	/**
	 * Encode stream $in to stream $out.
	 *
	 * QP encoded strings have a maximum line length of 76 characters.
	 * If the first line needs to be shorter, indicate the difference with
	 * $firstLineOffset.
	 *
	 * @param Swift_OutputByteStream $os output stream
	 * @param Swift_InputByteStream $is input stream
	 * @param integer $firstLineOffset
	 * @param integer $maxLineLength
	 */
	public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
	{
		if ($maxLineLength > 76 || $maxLineLength <= 0) {
			$maxLineLength = 76;
		}

		$thisLineLength = $maxLineLength - $firstLineOffset;

		$this->_charStream->flushContents();
		$this->_charStream->importByteStream($os);

		$currentLine = '';
		$prepend = '';
		$size = $lineLen = 0;

		while (false !== $bytes = $this->_nextSequence()) {
			// If we're filtering the input
			if (isset($this->_filter)) {
				// If we can't filter because we need more bytes
				while ($this->_filter->shouldBuffer($bytes)) {
					// Then collect bytes into the buffer
					if (false === $moreBytes = $this->_nextSequence(1)) {
						break;
					}

					foreach ($moreBytes as $b) {
						$bytes[] = $b;
					}
				}
				// And filter them
				$bytes = $this->_filter->filter($bytes);
			}

			$enc = $this->_encodeByteSequence($bytes, $size);
			if ($currentLine && $lineLen + $size >= $thisLineLength) {
				$is->write($prepend . $this->_standardize($currentLine));
				$currentLine = '';
				$prepend = "=\r\n";
				$thisLineLength = $maxLineLength;
				$lineLen = 0;
			}
			$lineLen += $size;
			$currentLine .= $enc;
		}
		if (strlen($currentLine)) {
			$is->write($prepend . $this->_standardize($currentLine));
		}
	}

	/**
	 * Get the name of this encoding scheme.
	 * Returns the string 'quoted-printable'.
	 *
	 * @return string
	 */
	public function getName()
	{
		return 'quoted-printable';
	}
}
